In particular, the invention relates to a process for manufacturing maleic anhydride from alcohols derived from the fermentation of renewable raw materials; preferably, the renewable raw materials are vegetable matter.
Maleic anhydride is generally obtained by oxidizing aromatic compounds, especially benzene, or by oxidizing alkanes, especially n-butane.
In recent years, essentially because of the growing awareness of the toxicity of benzene and the increase in the cost of producing it, pathways for the synthesis of maleic anhydride starting from other raw materials have been investigated. Benzene is in fact obtained from non-renewable raw materials of fossil origin (oil). However, oil resources are limited; extracting oil requires excavating deeper and deeper under tougher and tougher technological conditions, necessitating sophisticated equipment and the use of processes which consume more and more energy. These constraints have a direct consequence for the cost of manufacturing maleic anhydride.
Another synthesis pathway is currently more widely used, namely the oxidation of butane; however, butane is also obtained from oil and/or from natural gas fractions.
Advantageously and surprisingly, the inventors of the present application have developed a process for the industrial manufacture of maleic anhydride from renewable raw materials.
The process of the invention means that at least a portion of the raw materials of fossil origin can be dispensed with and replaced by renewable raw materials.
The maleic anhydride obtained using the process of the invention is of a quality such that it can be used in all applications where the use of maleic anhydride is known. In particular, the inventors have shown that it is possible to produce a maleic anhydride of higher purity by using the process of the invention, which uses renewable raw materials rather than raw materials of fossil origin.